Hubert Sauper, whose film "Darwin's Nightmare" was nominated for an Academy Award, talks about his latest, "We Come as Friends." In the immediate aftermath of South Sudan's independence, Hubert Sauper piloted a tiny, homemade prop plane into remote areas of the new country. He was mining for stories in a land trapped in the past but careening toward an apocalyptic future. The result is "We Come as Friends," which yields shocking and profound insights into the continuing impact of imperialism and colonialism in the region.